<i>Edging thermodynamic equilibrium</i> : mystical experiences as “mirror” encounters between the entropic brain and the entropic world

In active inference, mystical experiences (MEs) could be characterized as adaptive learning events, where the ordinary expectations of an agent become challenged or change permanently. In the context of psychedelic-induced MEs, these (temporary) changes in information processing have been attributed to increased brain entropy, the effects of which have been seen to reorganize deep perceptual-cognitive preferences (i.e. priors, e.g. an agent’s very sense of self). Adaptive (hyper)prior restructuring is an agent’s best survival strategy against environmental entropy: organisms survive by effectively predicting their future states. (Psychedelic) MEs, if characterized by increased brain entropy, may represent a state where sensory input and predictive output significantly overlap, leading to what is often phenomenally reported as a sense of “unity.” This possible alignment between sensorial entropy and entropic attunement could be understood evolutionarily as an adaptive strategy for the management of uncertainty, potentially explaining the profound nature of these experiences, where fundamental aspects of active inference come to a “halt,” delivering perplexity. This article explores how these experiences, framed as evolved allostatic adaptation, can be analyzed as information exchanges between systems where the discrepancies between the sensed and the predicted can be understood as radically altered, which we speculate is what phenomenally translates to cognitive effects such as higher ambiguity tolerance: a trademark of (psychedelic) MEs, but also death acceptance, aspects of dreams or psychosis, and comparable so-called “primary state” phenomena.